Icon A5 completes spin-resistance testing

This milestone will make the A5 the first production aircraft in history to be designed to and completely comply with the FAA’s full-envelope Part 23 spin-resistance standards developed from NASA’s work on the topic, according to officials with the Los Angeles-based company.

Spin resistance is a major safety-enhancing feature for light aircraft and can significantly reduce the number of loss-of-control accidents resulting from stall/spin scenarios, officials add. About 70% of all general aviation accidents are attributed to “Pilot Related Factors,” making them the most significant cause of fatal accidents, according to the Aircraft Owners and Pilots Association (AOPA) Air Safety Institute’s 2010 Nall Report. The report also found that as much as 41% of these pilot-related fatal accidents are due to stall/spin loss-of-control scenarios.

The FAA requires that Light Sport Aircraft must be either “spin recoverable” or “spin resistant.” While virtually all light aircraft in production today are “spin recoverable,” Icon chose to design the A5 to the more difficult to achieve but safer standard of “spin resistant,” company officials said. Additionally, the company chose to complete the tests to the rigorous FAA Part 23 standard for certified aircraft. Globally recognized spin-test pilot Len Fox flew the test flights, which included over 360 test cases with a wide range of control positions, power settings, and centers of gravity.

“The ultimate goal of spin resistance is to provide an aircraft that is stable and controllable in roll and yaw when held in a stall, even with adverse control inputs,” said Icon Aircraft VP of Engineering Matthew Gionta. “We’re excited to announce that after many months of exhaustive design and flight testing, the A5 has achieved this standard.”

Icon’s spin-resistant design is based on work done at NASA during the 1970s and 1980s. Using results from those studies as a base, Icon engineers created a cuffed wing design that employs multiple proprietary airfoils across the span of the wing. Additionally, these specialized airfoils used for spin resistance were not suited to the no-flap wing design Icon had previously planned to use on the A5, so Icon engineers chose to reintroduce wing flaps to preserve takeoff performance on the water.

“Other production aircraft have attempted to achieve spin resistance to the Part 23 standard, but no conventional production aircraft without canards has ever completely succeeded due to the sheer complexity of this problem,” Gionta added. “Although there are other aircraft that have incorporated some spin-resistance characteristics, such as the Ercoupe, Jetcruzer, Cirrus SR20/22, and Cessna Corvalis, the A5 will be unique for being the only production aircraft in history to be designed to and completely comply with the full-envelope Part 23 spin-resistance standard.”